Level 1 of Regenerate gives you a reasonable boost. I didn't bother with higher levels (with a lower return on investment), since once my ranger got a high enough level to be able to afford boosting other than the main ranger skills, the extra healing rate wasn't really needed. I'm planing on starting an unarmed warrior character someday, and will probably boost Regenerate and Life Leech.
In DKS I found most veins will offer you 2 malachite gems within 2 or 3 minutes of reloading. In FoV some quests can have malachite gems as a possible quest reward. Between malachite veins and reloading up to 3 or 4 times turning in quests (with multiple quest rewards), I finished the game with 65 gems (having used 2 for healing auras and 2 for the blind philosopher in the fjords).
Next game I'm either going to have to use more healing auras and level 10 enchantments, or not bother reloading.
I do the same with weapon enchantments; for a third slot there isn't a big difference, but I went with Butcher with my ranger in DKS, and Poison with my warrior in D2:ED.
For armour I went primarily with Life Line, and then Increased Mana, unless I was particularly vulnerable to a type of damage, in which case I would add one of the protection auras. If you are not dying a lot, running out of mana or using a lot of potions, then you have enough hit points and mana, so your enchantment choices are fine.
